Virtual Reality (VR) systems have become commonplace in computer graphics research labs. This technology, however, has yet to achieve widespread consumer use. Most virtual reality systems employ specialized display systems such as “VR goggles”, “VR helmets” and “heads-up displays” to achieve a greater sense of immersion into the virtual surroundings. Such a display system may be implemented as a helmet to continuously place a high-resolution display directly in front of a user's eyes. A system will also typically have a host processing system that is capable of delivering high performance 3D graphics at interactive frame rates.
The helmet can be equipped with a location and orientation tracking device. Such devices can produce a six dimensional description of the helmet wearer's approximate 3-space location and orientation. The six dimensions are recorded as position (x, y, z) and orientation (azimuth, elevation, roll). This information can be transmitted on the order of tens or hundreds of times per second to the host processor and used to dynamically update the 3D images being displayed in the helmet. The result is that when the user moves his head in the real world, the system displays an image that simulates the user moving his head in the virtual world. The system can give the user the sensation of being able to walk around and observe the virtual world. The interaction in the virtual world is “natural” because it is driven by natural movements in the physical world.
One technology for implementation employs a three-dimensional electromagnetic field emitter mounted in the ceiling. The helmet has a receiver that is able to read the magnetic field and determine the receiver's location and orientation. The receiver then sends this data to the host computer via a serial cable.
However, despite the advantages of current virtual reality technology, it has several drawbacks. First, restrictions in location are quite severe, dramatically limiting where the technology may be used. A virtual reality system typically requires a dedicated room to house the system and the electromagnetic field generators. Additionally, the display and tracking system often requires a fixed length cable to connect it to the host system that performs the display rendering and position processing. Therefore, such systems are inherently non-portable.
Another problem is that VR helmets can be physically uncomfortable. Many helmets are too heavy to be worn for long periods of time. Additionally, VR simulator sickness is a frequently reported problem. Proposed solutions to the simulator sickness problem entail giving the user a visual cue of the real world (either an overlaid small video window of the real world or synthetic objects that remain anchored with respect to the real world). Further, current display types often strain the user's eyes, as they require long periods of near distance focus. Also, many users are not prone to spending so much time immersed in a powerful electromagnetic field.
Lastly, there are social stigmas attached to wearing VR helmets. Helmet wearers may feel uncomfortable or strange wearing a heads-up display in front of other people. It is hard to see other people when wearing these devices, thereby reducing social contact. The converse is also true; people may feel uncomfortable interacting with persons wearing VR helmets.